Crocidura phanluongi, Jenkins, Paulina D., Abramov, Alexei V., Rozhnov, Viatcheslav V. & Olsson, Annette, 2010

Jenkins, Paulina D., Abramov, Alexei V., Rozhnov, Viatcheslav V. & Olsson, Annette, 2010, A new species of Crocidura (Soricomorpha: Soricidae) from southern Vietnam and north-eastern Cambodia, Zootaxa 2345, pp. 60-68 : 61-66

Crocidura phanluongi sp. nov.

Holotype. ZIN 97092, collector’s number 24, male, body in ethanol, skull extracted, collected 26 June 2007 by A.V. Abramov.

Type Locality. Northern portion of Yok Don National Park, Dak Lak Province, Vietnam, 12° 58' N, 107° 49' E, altitude 250 m a.s.l..

Paratypes. ZIN 97090, collector’s number 15, female, collected 23 June 2007; ZIN 97091, collector’s number 23, female, collected 26 June 2007; ZIN 97093, collector’s number 30, female, collected 28 June 2007; all bodies in ethanol, skulls extracted, collected by A.V. Abramov from the same locality as the holotype.

Referred material. ZIN 97089, collector’s number 3, male, collected 10 June 2007 by A. V. Abramov from Binh Chau – Phuoc Buu Nature Reserve, Ba Ria – Vung Tau Province, Vietnam, 10° 32' N, 107° 29' E, altitude 50 m a.s.l.; ZMMU S- 162801, male and ZMMU S- 162802, female, both collected September 1994 by N. V. Belyaeva and M. V. Kalyakin from Ma Da Forest, Dong Nai Province, Vietnam, 11° 18' 50" N, 107° 04' 18" E, altitude 50 m a.s.l.; all bodies in alcohol, skulls extracted.

BM(NH) 2008.718, collector’s number CCP-AO 0 0 77, female; BM(NH) 2008.719, collector’s number CCP-AO 0 0 78, female; BM(NH) 2008.720, collector’s number CCP-AO 0 0 79, male; BM(NH) 2008.721, collector’s number CCP-AO 0 0 80, sex unknown; BM(NH) 2008.722, collector’s number CCP-AO 0 0 82, female; BM(NH) 2008.723, collector’s number CCP-AO 0 0 83, sex unknown; all collected 22 – 23 June 2006 by Annette Olsson from Virachey National Park, North East Cambodia 14° 18' 49" N 107° 22' 5" E, altitude 480 m a.s.l.; all bodies in alcohol, skulls extracted. See Figure 1 for a map of collection localities.

Etymology. The new species is named in honour of the late Dr. Phan Luong (1948 – 2008). From 1990 he directed the ecological researches of the Joint Vietnam - Russian Tropical Research and Technological Centre, Hanoi. During the last 20 years, he organised many Vietnamese - Russian biodiversity surveys, including his last fieldwork in Yok Don and Binh Chau – Phuoc Buu National Parks in 2007.

Diagnosis. A small to medium sized shrew distinguished from similar sized species recorded from Vietnam and Cambodia by the following combination of characters: skull with a narrow interorbital region relative to maxillary and braincase breadth, upper third molar slender, and lower third molar with a simple talonid, reduced to a hypoconid.

Description. A small to medium sized shrew (see Table 1 ), with a moderately long tail, 61 – 83% of head and body length. Dorsal pelage dark grey, grading into the slightly paler ventral pelage (see Fig. 2 ). The tail is similarly coloured to the body, slightly paler below, with bristle hairs present on the proximal two thirds to three quarters of its length. The dorsal surfaces of the fore and hind feet are markedly paler than the body. Skull (see Fig. 3 ) with a slender rostrum and zygomatic region but a broad maxillary region; interorbital region narrow, braincase moderately narrow and short with prominent angled superior articular facets and well developed lambdoid crests.

The first upper incisor (I1) is moderately slender and the posterior cusp is broad, approximately one third the height of the first unicuspid (Un1). The second unicuspid (Un2) is only slightly smaller than the third (Un3) and subequal in height. The parastyle of the upper premolar (P4) is small, approximately half the height as Un3; the lingual border of the tooth is nearly parallel to the medial axis of the skull, with the hypocone only slightly more lingually positioned than the protocone; the posterolingual border of the tooth is shallowly concave. The talon of the third upper molar (M3) is narrow. Lower incisor with two denticulations evident in unworn dentition. A trace of a posterolingual cuspid is present on the lower premolar (p4). The talonid of the third lower molar (m3) is simple (see Fig. 4 ) and reduced to a hypoconid, lacking other elements, although it may show a wear facet.

Variation. In specimens from Virachey National Park, Cambodia the dorsal pelage is grey brown, the ventral pelage contrasting silvery grey, with the light coloured venter grading into the dorsal colour on the flanks, or showing moderately sharp demarkation in some specimens. Fore and hind feet markedly paler in coloration than the body; limbs light buffy grey, digits cream. Tail grey above, lighter below, bicolored at least proximally in all specimens and for the greater part of the length in others. Bristle hairs present on the proximal two thirds of the length, with silver hairs at the tip.

The specimen from Binh Chau – Phuoc Buu has a slightly shorter tail (61% of head and body length) than specimens from other localities (68 – 83%). Specimens from Yok Don and Binh Chau – Phuoc Buu average smaller in condylobasal and upper toothrow length than those from Ma Da and Virachey, and specimens from Yok Don have narrower braincases than specimens from other localities (see Table 2 ).

Character Yok Don Binh Chau Ma Da Virachey Comparisons. The tabular key ( Table 3 ) shows that the new species is considerably smaller than most species of Crocidura recorded from Vietnam, namely C. fuliginosa , C. attenuata and C. sokolovi , and smaller than C. phuquocensis . It is larger than C. wuchihensis , C. kegoensis and C. zaitsevi .

It is comparable in size to C. indochinensis but differs in a number of features. Externally the two species are distinguished by the tail length, which is longer relative to head and body length and to condyloincisive length in C. indochinensis than in C. phanluongi (see Table 1 ). The cranium of C. phanluongi has a narrower interorbital region relative to maxillary breadth and to braincase breadth than that of C. indochinensis (see Fig.3 and Table 1 ). The talon of M3 is slender relative to the size of M 2 in C. phanluongi in comparison to that of C. indochinensis in which the talon is relatively larger. In contrast to the simple talonid of m 3 in C. phanluongi , that of C. indochinenesis is complex, with all elements, hypoconid, entoconid, entoconid ridge and talonid basin present (see Fig. 4 ).

Distribution. The species seems to have a fairly widespread distribution, potentially ranging across three ecoregions as defined by Wickramanayake et al. (2002). Both Virachey National Park and Ma Da Forest, lie within the non-montane Ecoregion 59: Southeastern Indochina dry evergreen forests. Yok Don National Park is classified as Ecoregion 72: Central Indochina Dry Forests, whereas Binh Chau – Phuoc Buu Nature Reserve, described by Wickramanayake et al. (2002) as an area of low rolling hills containing a variety of dry forest communities, is in Ecoregion 58: Southern Vietnam Lowland Dry Forests.

The series of type specimens was collected from a variety of habitats in the northern portion of Yok Don National Park: disturbed dipterocarp forest; mixed evergreen forest near a small stream; in bamboo forest; and at the edge of mixed forest near the top of a small hill. The specimen from Binh Chau – Phuoc Buu Nature Reserve was collected in a small area of wetland surrounding a narrow brook in a vast sandy area with Melaleuca forest. The Ma Da Forest where the two other Vietnamese specimens were collected, is a large dipterocarp forest. From these specimens it appears that the new species is widely distributed in lowland areas of southern Vietnam (see Fig. 1 ).

Crocidura recorded from Vietnam, including the new species C. phanluongi .

In contrast the specimens from Virachey National Park, Cambodia were collected in a steep valley, amongst many large rocks in the understory of evergreen hill forest, 15 metres from a river, at an higher altitude (480 m a.s.l.). The forest was very dense with a closed canopy. The end of June, when the shrews were collected, is the rainy season, with heavy rainfall expected every day, especially in mountain areas such as Virachey National Park.

Figures

FIGURE 1. Map of collection localities of Crocidura phanluongi. Cambodia: 1. Virachey National Park. Vietnam: 2. Yok Don National Park; 3. Ma Da Forest; 4. Binh Chau – Phuoc Buu Nature Reserve.

FIGURE 2. Photograph of adult female Crocidura phanluongi (ZIN 97090).

FIGURE 3. Comparison of crania of Crocidura phanluongi (ZIN 97090) and Crocidura indochinensis (ZIN 97671). Top row: dorsal and ventral views of the skulls of Crocidura indochinensis (left) and Crocidura phanluongi (right). Second row: left lateral view of skull and mandible of Crocidura indochinensis. Bottom row: left lateral view of skull and mandible of Crocidura phanluongi.

FIGURE 4. Lower right third molar of Crocidura phanluongi (BM (NH) 2008.722) on the left and Crocidura indochinensis (ZIN 97671) on the right. Scale 1 mm.

Tables

TABLE 1. Comparison of external and cranial measurements of Crocidura phanluongi and C. indochinensis. Measurements in millimetres are presented as the mean and standard deviation, range and number of specimens in parentheses.

Character	C. phanluongi	C. indochinensis
Head and body length	59.6 ± 4.33 54 – 66 (13)	64.3 ± 2.92 59 – 68 (9)
Tail length	44.4 ± 2.32 40 – 48 (13)	55.0 ± 2.96 50 – 58 (9)
Hindfoot length	11.7 ± 0.69 10 – 12 (13)	12.2 ± 0.43 12 – 13 (9)
Condylobasal length	17.4 ± 0.47 16.8 – 18.1 (12)	17.5 ± 0.33 16.9 – 17.8 (9)
Upper toothrow length	7.7 ± 0.3 7.3 – 8.2 (13)	7.7 ± 0.24 7.3 – 8.0 (9)
Maxillary breadth at M2	5.3 ± 0.19 5.1 – 5.8 (13)	5.2 ± 0.07 5.1 – 5.3 (9)
Least interorbital breadth	3.6 ± 0.16 3.4 – 3.9 (13)	4.0 ± 0.09 3.9 – 4.2 (9)
Braincase breadth	7.9 ± 0.24 7.5 – 8.2 (12)	8.2 ± 0.15 7.9 – 8.4 (9)
Braincase height	4.4 ± 0.19 4.1 – 4.7 (12)	4.4 ± 0.11 4.2 – 4.5 (9)
Braincase length	7.0 ± 0.27 6.6 – 7.4 (12)	7.3 ± 0.14 7.2 – 7.5 (9)
Ratio of tail length to head and body length	0.75 ± 0.06 0.61 – 0.83 (13)	0.86 ± 0.04 0.81 – 0.92 (9)
Ratio of tail length to condyloincisive length	2.47 ± 0.13 2.25 – 2.74 (13)	3.04 ± 0.13 2.85 – 3.19 (9)
Ratio of interorbital breadth to maxillary breadth at M2	0.68 ± 0.02 0.65 – 0.71 (13)	0.77 ± 0.02 0.75 – 0.79 (9)
Ratio of interorbital breadth to braincase breadth	0.45 ± 0.01 0.43 – 0.48 (12)	0.49 ± 0.01 0.47 – 0.5 (9)

TABLE 2. Variation in Crocidura phanluongi. Measurements in millimetres are presented as the mean and standard deviation, range and number of specimens in parentheses.

Condylobasal length 17.0 ± 0.24 17.2 16.8 – 17.3 (4)	18.1	17.6 ± 0.36 17.1 – 18.1 (6)
Upper tooth row length 7.5 ± 0.16 7.3 7.3 – 7.6 (4)	7.8, 8.1	7.9 ± 0.23 7.6 – 8.2 (6)
Braincase breadth 7.7 ± 0.15 8.2 7.5 – 7.9 (4)	8.2	8.0 ± 0.12 7.9 – 8.2 (6)

TABLE 3. Tabular key of morphological measurements (range in millimetres or percentage) to distinguish the species of

Character	Crocidura fuliginosa	Crocidura attenuata	Crocidura sokolovi	Crocidura indochinensis	Crocidura phanluongi	Crocidura wuchihensis	Crocidura phuquocensis	Crocidura zaitsevi	Crocidura kegoensis
Head and body length	79–107	67–83	70–78	59–68	54–66	55–65	68–72	48–58	48
Tail length as % of head and body length	59–91	63–76	87–93	81–92	61–83	59–85	69–87	62–81	56
Tail pilosity as % of tail length	50–60	50	<33	33	65–75	20	60	65	50
Condylo-basal length	21.3–23.4	18.8–21.2	18.8–20.4	16.9–17.8	16.8–18.1	15.0–16.4	17.6–18.2	14.2–15.3	14.9
Upper tooth row length	9.8–10.8	8.2–9.6	8.3–9.2	7.3–8.0	7.3–8.2	6.4–7.2	7.7–8.0	6.2–6.8	6.5
Ratio of interorbital breadth to maxillary breadth at M2	0.67–0.75	0.69–0.78	0.79–0.82	0.75–0.79	0.65–0.71	0.72–0.83	0.7–0.75	0.8–0.86	0.77